Conbercept for Treatment of Neovascular Age-related Macular Degeneration: Results of the Randomized Phase 3 PHOENIX Study

Abstract

Age-related macular degeneration (AMD) can cause irreversible vision loss leading to blindness. We aim to evaluate the efficacy and safety of intravitreal injections of 0.5mg conbercept, a new anti-vascular endothelial growth factor (anti-VEGF) drug, for treatment of AMD on a schedule more manageable for patients. A prospective, double-masked, multicenter, sham-controlled, phase III randomized trial. Patients: Patients with choroidal neovascularization (CNV) secondary to AMD were enrolled and randomized to the conbercept group or the sham control group. The conbercept group received intravitreal injections of conbercept (0.5mg) once monthly for the first 3months, then once quarterly until month 12 (3+ Q3M). The sham group received first 3monthly sham injections and then 3monthly injections of conbercept (0.5mg) followed by quarterly administrations until month 12. The primary endpoint was mean change from baseline in best-corrected visual acuity (BCVA) at month 3. A total of 114 patients (91.9%) from 9 sites in China completed the 12-month study. At the 3-month primary endpoint, the mean changes in BCVA from baseline were+9.20 letters in the conbercept group and+2.02 letters in the sham group, respectively (P< .001). At 12months, the mean changes from baseline in BCVA letter score were+9.98 letters in the conbercept group and+8.81 letters in the sham group(P= .64). The most common ocular adverse events were associated with intravitreal injections, such as conjunctival hemorrhage, and increased intraocular pressure. A conbercept dosing regimen of 3 initial monthly administrations followed by quarterly treatments is effective for treatment of AMD. In previous reports, other anti-VEGF agents were unable to maintain similar clinical benefits with the same regimen.